Control of root system architecture by DEEPER ROOTING 1 increases rice yield under drought conditions

First author: Yusaku Uga; Affiliations: National Institute of Agrobiological Sciences (农业生物资源研究所): Tsukuba, Japan

Corresponding author: Yusaku Uga

The genetic improvement of drought resistance is essential for stable and adequate crop production in drought-prone areas. Here we demonstrate that alteration of root system architecture improves drought avoidance through the cloning and characterization of DEEPER ROOTING 1 (DRO1), a rice quantitative trait locus controlling root growth angle. DRO1 is negatively regulated by auxin and is involved in cell elongation in the root tip that causes asymmetric root growth and downward bending of the root in response to gravity. Higher expression of DRO1 increases the root growth angle, whereby roots grow in a more downward direction. Introducing DRO1 into a shallow-rooting rice cultivar by backcrossing enabled the resulting line to avoid drought by increasing deep rooting, which maintained high yield performance under drought conditions relative to the recipient cultivar. Our experiments suggest that control of root system architecture will contribute to drought avoidance in crops.

干旱抗性的遗传改良对于易干旱地区保证作物的稳定、充足产量至关重要。本文中，作者克隆并验证了一个水稻中控制根生长角度的数量性状位点功能基因DRO1，该基因能够改变水稻的根系统结构，提升水稻干旱抗性。生长素负调控DRO1基因的表达，DRO1基因参与根尖组织中细胞的伸长，而这会导致根响应重力所引起的不对称生长和向下弯曲。DRO1基因的高表达会增加根向下弯曲的角度，从而导致根更加朝下生长。通过回交将DRO1基因引入到一个浅根系的水稻栽培种中，结果发现能够通过增加根的向下生长来避免干旱，从而相比于该品种正常水稻在干旱条件下获得更高的产量。本文的实验表明通过控制根系统的结构将有助于作物干旱抗性的育种。

通讯：Yusaku Uga (https://www.naro.affrc.go.jp/archive/nias/qtl/english/about_us.html)

个人简介：1998-2003年，筑波大学，博士。

研究方向：水稻数量性状的遗传和分子基础。

doi: https://doi.org/10.1038/ng.2725

Journal: Nature Genetics

Published date: August 04, 2013